Research Article |
Corresponding author: Rudolf H. Scheffrahn ( rhsc@ufl.edu ) Academic editor: Eliana Cancello
© 2023 Rudolf H. Scheffrahn, Tiago F. Carrijo.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Scheffrahn RH, Carrijo TF (2023) Chasitermes pax, a new genus and species of soldierless termite (Termitidae, Apicotermitinae) from the island of Trinidad. ZooKeys 1139: 127-136. https://doi.org/10.3897/zookeys.1139.94972
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Chasitermes pax Scheffrahn & Carrijo gen. et sp. nov. is described from workers collected from a single colony in the Northern Range of Trinidad. The shape and texture of the unsclerotized enteric valve, tubular shape of the enteric valve seating, and prominent spherical mesenteric tongue of C. pax are the diagnostic characters for both the genus and species. A Bayesian phylogenetic analysis using the COI gene and including all neotropical Apicotermitinae genera described to date supports the new genus as a distinct terminal.
Anoplotermes-group, enteric valve, Isoptera, Neotropics, new species, taxonomy
The soldierless termites of the New World form a monophyletic clade (
Trinidad and Tobago are continental islands that separated from Venezuela during the Holocene (
In this paper we describe Chasitermes pax gen. et sp. nov. based on the morphology of the worker caste and molecular data.
Workers were collected and preserved in 85% ethanol. External and internal dissections were suspended in Purell Instant Hand Sanitizer in a plastic Petri dish and photographed using a Leica M205C stereomicroscope controlled by Leica Application Suite ver. 3.0 montage software. The enteric valve (EV) was prepared by removing the entire worker proctodeal segment (P2) section in ethanol. Food particles were expelled from the P2 tube by pressure manipulation. The tube was quickly submerged in a droplet of PVA medium (BioQuip Products Inc.) which, by further manipulation, eased muscle detachment. The remaining EV cuticle was left intact or longitudinally cut, splayed open, and mounted on a microscope slide using the PVA medium. The EV was photographed with a Leica CTR 5500 compound microscope with phase-contrast optics using the same montage software. Terminology of the worker gut follows that of
The barcode region of the mitochondrial gene cytochrome c Oxidase subunit I (COI) of Chasitermes pax was obtained by DNA extraction and PCR performed by the Canadian Centre for DNA Barcoding (BOLD systems) following standard high-throughput protocols (
Chasitermes pax Scheffrahn & Carrijo, sp. nov.
The combination of unsclerotized rectangular EVA cushions, a tubular extension of EVS, and a prominent spherical mesenteric tongue make C. pax unique among all Apicotermitinae genera.
Imago unknown. Worker. (Figs
Max. | Min. | Mean | |
---|---|---|---|
Length of head to lateral base of mandibles | 0.77 | 0.70 | 0.73 |
Maximum head width | 0.93 | 0.82 | 0.85 |
Length of hind tibia | 0.77 | 0.67 | 0.72 |
Length of postclypeus | 0.25 | 0.18 | 0.21 |
Width of postclypeus | 0.44 | 0.39 | 0.40 |
Length of fore tibia | 0.67 | 0.53 | 0.60 |
Width of fore tibia | 0.18 | 0.12 | 0.15 |
Fore tibia width:length ratio | 0.30 | 0.21 | 0.25 |
The single most diagnostic character of the C. pax worker is the enteric valve armature which has unsclerotized rectangular cushions composed of creased or fringed scales. The tubular extension of the EVS in C. pax is closest to Patawatermes nigripunctatus (Emerson, 1925) but is much longer in the former and P. nigripunctatus lacks a trilobed enteric valve seating. The left mandible of C. pax has prominent premolar process closest to Patawatermes turricola (Silvestri, 1901) but it is narrower and longer in the former.
Named in honor of the collector, James A. Chase.
Tunapuna, island of Trinidad.
Republic of Trinidad and Tobago, Tunapuna (10.667, -61.396), elev. 248 m, 4JAN2012, J. Chase, UFTC no. TT2188 holotype worker and about 75 additional workers.
As described for the genus.
The species is named for the Pax Guest House where we stayed during our expeditions to Trinidad. It is on the tranquil and inspirational property of the Mount Saint Benedict Abby which encompasses the type locality of C. pax. “Pax” is latin for “peace”, and represents a noun in apposition.
The C. pax workers were collected under a stone. Gut contents confirm that C. pax feeds on soil organic matter. So far, this species is only known from the Northern Range on the island of Trinidad.
The gene tree recovered Chasitermes pax as sister group to Rubeotermes, but with very low posterior probability. The low branch support for most major clades in the neotropical Apicotermitinae should be interpreted as a polytomy (Fig.
Advances in the taxonomy, phylogeny, biogeography, ecology of the Apicotermitinae are ongoing (
The authors thank Jim Chase for his uncompromising, energetic, and enthusiastic attitude toward termite collection over a span of more than 25 years. TFC was funded through a grant from São Paulo Research Foundation (FAPESP, #2020/06041-4).